The Parent Grant explores the finding that one or more regions of classic auditory association cortex posterior to A1 are sites of multisensory convergence, in that, they respond to somatosensory stimuli, as well .as sounds. This surprising finding disputes a prevailing view that multisensory integration is confined to specialized, higher order "association" structures. It also bears on the fundamental question of whether auditory and somatosensory systems have "what" and "where" divisions like those proposed for the visual pathways. Anatomical tracer studies, in conjunction with standard multiunit/single unit mapping procedures in anesthetized monkeys and with multielectrode studies in awake monkeys will address 1. the relationship of somatosensory representation to previously defined auditory fields. 2. the anatomical source(s) of somatosensory input. 3. the functional significance of auditory-somatosensory co- representation. This FIRCA Project will conduct an analysis supplementary to number 3 above. We will address 1)the physiological impact of somatosensory input in auditory cortex, targeting somatosensory source sites identified by the parent grant 2) the hierarchial relationships between somato-recipient regions of auditory cortex and the somatosensory input sources and 3) expansion of physiological findings by anatomical reconstruction of the projections between selected somatosensory "input" and auditory "recipient" site pairs identified by Specific Aim 1.